Large non-domesticated mammals are typically sedated or immobilized for reasons of medical examination or treatment, or for reasons of physiologic or morphologic study, herd health assessment, or animal relocation, or as matter of protecting public safety. The non-domesticated nature of the animals makes it impossible to approach or safely handle them without sedation or immobilization, even in captive environments such as zoological parks or animal preserves. Performing any procedure that produces pain is also impossible unless the animal is heavily sedated or provided with analgesia, because the animal will resist such a procedure, even if the animal is substantially confined or physically restrained.
The sedating or immobilizing agent should be medically safe for administration to the animal. Mortality is usually not an acceptable outcome of any medical or scientific study, examination or relocation activity. The sedating and immobilizing agent should not create undesirable physiological side effects, such as significant body temperature variations, hyperthermia, muscle rigidity and excitement, among other things. Significant muscle rigidity, despite sedation and immobilization, makes it impossible, difficult or dangerous to conduct a treatment or examination or to move the animal.
Animal and public safety also involves achieving complete or near-complete reversibility of the sedated and immobilized state, without a prolonged recovery time. Since a free-ranging non-domesticated animal will usually be released into the natural environment after sedation or immobilization, the animal should be able to respond to flight-invoked stimulus and to protect itself naturally, both of which are compromised if the animal remains partially sedated. A prolonged sedated condition creates a risk of death or injury from its natural predators or from failing to successfully negotiate natural environmental hazards, such as cliffs and bodies of water, or a potential threat to public safety.
It is important to be able to administer the sedating or immobilizing agent from a remote distance by a dart. Non-domesticated animals cannot be approached for injection by hand without fleeing. The flight distance which a non-domesticated animal will tolerate varies with the species and the environment. Darts are used under such circumstances to inject the animal from a remote distance of up to about 70 meters. Shooting or projecting the dart should be accomplished with reasonable accuracy to assure that the dart will inject the drug into the muscle mass of a shoulder or hind quarter of the animal. Impacting the dart in a bony area such as the rib cage or lower extremity will not allow the needle of the dart to penetrate sufficiently to deliver the full dose of the sedating or immobilizing agent. To ensure an adequate projection distance and good accuracy in aiming its placement, the dart must be relatively small. A relatively small dart is capable of carrying only a relatively small volumetric quantity of the sedating or immobilizing agent. Consequently, a small volume of the agent must have adequate potency to accomplish the desired effect.
The factors involved in successfully immobilizing non-domesticated free-ranging and confined mammals are described in U.S. Pat. No. 7,795,263. This US patent describes an advantageous pharmaceutical combination of butorphanol tartrate, azaperone tartrate and medetomidine hydrochloride (BAM), which is effective in achieving desirable effects and reducing undesirable effects when immobilizing many different species of animals.
One disadvantage associated with BAM, and most other known immobilizing pharmaceutical agents for non-domesticated animals, is that these agents utilize opioids or other types of drugs which involve a significant risk of human abuse. Because of their potential for human abuse, governmental drug regulatory agencies, such as the United States Drug Enforcement Administration (DEA), impose strict regulatory controls on the use and conditions of use of such pharmaceutical agents, including strict penalties for violation of these regulations. For example, governmental regulations require a Doctor of Veterinary Medicine to administer or oversee the administration of these drugs to animals. The regulations also require a precise and complex accounting of the amount of each drug administered and the amount of each drug kept on hand. The regulations also impose strict requirements on keeping the drugs secure from theft, which practically means that the drugs must be kept in locked safes.
Strict governmental regulations may be more readily complied with in a zoological park which typically has a veterinarian available to administer or oversee the administration of the drugs. Furthermore, the animals are kept in a relatively small and confined geographical area where the veterinarian may quickly and conveniently access the animal. A zoological park usually possesses the necessary safe and other physical facilities for safekeeping the drugs and keeping records of their administration. However, in those circumstances where the non-domesticated mammals are free-ranging in government or privately-owned wildlife preserves, or in herds in very large confinement areas, the task of overseeing and caring for the animals is typically undertaken by trained technicians and biologists who are not veterinarians. These non-veterinarians need to sedate or immobilize animals in the wild or in open areas under circumstances where it is not practical or possible logistically to call for the services of a veterinarian and then wait for his or her arrival before the immobilizing drug is administered. Under such circumstances, or under circumstances where the regulatory compliance and administration burden is so substantial as to be prohibitory from a practical standpoint, there is no completely satisfactory unscheduled (not subject regulatory control) immobilizing agent or combination which can be administered to non-domesticated mammals across a wide range of species.